I upgraded gdal to 1.10 and used r.in.gdal -l and was able to read the file and display it with no problems.
Thanks, Lee On Feb 13, 2014, at 5:35 PM, Hamish <[email protected]> wrote: > (sorry for top posting, no time to deal with yahoo mail today) > > Hi, > > note for GRIB you need gdal 1.10 or newer, there were > edge coordinate bugs in earlier versions. > > > ---> see: http://grasswiki.osgeo.org/wiki/GRIB > > > note grass uses the cell-center for data value convention, > not the data values at grid line confluences (nodes) convention for raster > arrays. > > > and so in grass the region's e,w,s,n values are at the outer edge of the > raster cells, while gridline-centered arrays* would give coords overhanging > the edges of the region by half a cell. > > sometimes when loading in gridline-centered data you need to crop away the > data row at 90N,S and one of the two at 0,360 or +-180 longitude. See the > MODIS page in the wiki perhaps. > the way there is to use 'r.in.gdal -l' to force it to fit into 90N,S, then > carefully use g.region + r.mapcalc to crop away the two rows, then use > r.region to fix the map bounds back to where they should. > > resolution ends up with bounds at e.g. 25,75m with a cell size of 50m, you > have to be careful that d.zoom or 'g.region -a' doesn't realign the bounds to > 0,50,100m instead of 25,75 (so silently shifted by 1/2 a cell). > > > > * (usually can spot them as they have like 501x1001 cells not 500x1000) > > > > http://grasswiki.osgeo.org/wiki/GRASS_raster_semantics#Cell_Locations > > http://grasswiki.osgeo.org/wiki/GRASS_FAQ#Errors > > > but the first thing to verify for the GRIB format is that your gdal version > is 1.10 or newer. > > > regards, > > Hamish > > > On Wednesday, February 12, 2014 6:21 PM, Lee Eddington > <[email protected]> wrote: > > I’m trying to import some GRIB2 data into GRASS (6.4.3 on a Mac) and am > having a problem with the range of the latitude coordinates. I’m working > with the following file: >> >> >> http://www.ftp.ncep.noaa.gov/data/nccf/com/gfs/prod/gfs.2014021112/gfs.t12z.master.grbf72.10m.uv.grib2 >> >> I used gdal_translate to create a GeoTiff file, but when I try to import it >> into a lat/lon location I get the following: >> >> GRASS 6.4.3 (GFS_from_grib):~ > r.in.gdal >> input=gfs.t12z.master.grbf72.10m.uv.tif output=gfs >> WARNING: Datum <unknown> not recognised by GRASS and no parameters found >> Projection of input dataset and current location appear to match >> WARNING: G_set_window(): Illegal latitude for North >> >> Here is the output from gdalinfo: >> >> lees-mbp:GFS Lee$ gdalinfo gfs.t12z.master.grbf72.10m.uv.tif >> Driver: GTiff/GeoTIFF >> Files: gfs.t12z.master.grbf72.10m.uv.tif >> gfs.t12z.master.grbf72.10m.uv.tif.aux.xml >> Size is 720, 361 >> Coordinate System > is: >> GEOGCS["Coordinate System imported from GRIB file", >> DATUM["unknown", >> SPHEROID["Sphere",6371229,0]], >> PRIMEM["Greenwich",0], >> UNIT["degree",0.0174532925199433]] >> Origin = (-0.250000000000000,90.250000000000000) >> Pixel Size = (0.500000000000000,-0.500000000000000) >> Metadata: >> AREA_OR_POINT=Area >> Image Structure Metadata: >> INTERLEAVE=PIXEL >> Corner Coordinates: >> Upper Left ( -0.2500000, 90.2500000) ( 0d15' 0.00"W, 90d15' 0.00"N) >> Lower Left ( -0.2500000, -90.2500000) ( 0d15' 0.00"W, 90d15' 0.00"S) >> Upper Right ( 359.750, 90.250) (359d45' 0.00"E, 90d15' 0.00"N) >> Lower Right ( 359.750, -90.250) (359d45' 0.00"E, 90d15' 0.00"S) >> Center ( 179.7500000, 0.0000000) (179d45' 0.00"E, 0d 0' 0.01"N) >> Band 1 > Block=720x1 Type=Float64, ColorInterp=Gray >> Description = 10[m] HTGL="Specified height level above ground" >> Metadata: >> GRIB_COMMENT=u-component of wind [m/s] >> GRIB_ELEMENT=UGRD >> GRIB_FORECAST_SECONDS=259200 sec >> GRIB_PDS_PDTN=0 >> GRIB_PDS_TEMPLATE_NUMBERS=2 2 2 0 96 0 0 0 1 0 0 0 72 103 0 0 0 0 10 255 >> 0 0 0 0 0 >> GRIB_REF_TIME=1392120000 sec UTC >> GRIB_SHORT_NAME=10-HTGL >> GRIB_UNIT=[m/s] >> GRIB_VALID_TIME=1392379200 sec UTC >> Band 2 Block=720x1 Type=Float64, ColorInterp=Undefined >> Description = 10[m] HTGL="Specified height level above ground" >> Metadata: >> GRIB_COMMENT=v-component of wind [m/s] >> GRIB_ELEMENT=VGRD >> GRIB_FORECAST_SECONDS=259200 sec >> GRIB_REF_TIME=1392120000 sec UTC >> > GRIB_SHORT_NAME=10-HTGL >> GRIB_UNIT=[m/s] >> GRIB_VALID_TIME=1392379200 sec UTC >> >> So it’s showing the north and south bounds of 90.25 N and -90.25 S. I’m >> almost positive that this would be the values of the edges of the cells and >> that the cells are centered at 90 N and 90 S. >> >> Is there a way to import this data? >> >> Thanks, >> Lee >> >> _______________________________________________ >> grass-user mailing list >> [email protected] >> http://lists.osgeo.org/mailman/listinfo/grass-user >> >> _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
